基于SLAF-seq技术鉴定甘蓝型油菜叶缘裂刻性状候选基因

Identi?cation of Candidate Genes for Lobed-leaf Trait in Brassica napus L. by SLAF-seq Method

叶缘裂刻性状是甘蓝型油菜遗传育种的理想形态标记。叶缘裂刻性状变异材料的创建对丰富甘蓝型油菜叶片形态和优良品种改良至关重要。本研究以甘蓝型油菜常规品种中双11和甘蓝型油菜叶缘裂刻新品系Y176为亲本(通过甘蓝型油菜与菜远缘杂交获得),从F2群体中分别挑选出叶缘裂刻和正常叶形的植株各50株,构建了两个极端性状混池DNA文库,借助SLAF-seq-BSA技术,挖掘甘蓝型油菜叶缘裂刻性状相关候选基因。共开发出177941个SLAF标签,通过分析SLAF标签的多态性,共获得150168个SNP,其中亲本间共获得128200个SNP。对ED方法和SNP-index方法得到的关联区域进行综合分析,获得1个与目标性状紧密关联的候选区域,位于甘蓝型油菜A10染色体上的14528149～17353693区域,总长度为2.83 Mb,约有666个编码基因。与前人研究定位在同一染色体上,但本研究定位的区间与前人研究不同,说明本研究存在控制叶缘裂刻新基因的可能性大。并对该区域内基因进行功能注释,其中666个注释到NR数据库;517个注释到SwissProt数据库;587个注释到GO数据库;151个注释到KEGG通路;258个注释到COG数据库,对候选基因进行注释有助于进一步分离相关基因。

Lobed-leaf is widely known as an ideal morphological marker in rapeseed breeding.Genetic variation of lobed-leaf plays an important role in enriching the leaf shape diversity and improving genetic breeding of rapeseed.In this study,fifty plants with normal leaf and 50 plants with lobed-leaf were selected from the F2 population respectively,which was derived from a cross of the normal leaf line Zhongshuang No.11 and the leaf-lobed new line Y176.Two bulked DNA pools were generated,which were subjected for SLAF-seq-BSA(specific-locus amplified fragment sequencing and bulked segregant analysis).A total of 177941 labels were obtained and 150168 SNPs were identified,including 128200 SNPs that were polymorphic between both parents.A physical interval expanding 2.83 Mb on chrA10(14528149~17353693 bp)was tightly associated with lobed-leaf trait.Within that,666 candidate genes was found.Since the genetic confidence interval of this locus differed to the physical positions of previously reported genes,there might be a new gene controlling leaf margin cleavage.Furthermore,666,517,587,151 and 258 genes in this region were annotated by NR,Swiss-Prot,GO,KEGG and COG databases,respectively.Thus,this information might be helpful in future map-based gene isolation of lobed-leaf in Brassica napus L..